Cables for detecting location of liquids are used e.g. in the monitoring of liquids in storage and transport, which might have harmful effects on the environment, particularly on air, soil, and ground water. This includes e.g. pipelines or tanks for oils, propellants, and chemicals of various kinds. Cables for this purpose are known, in which the electrical characteristics change in the area of the liquids to be located. These changes are mechanically detected and serve to define the position of the leakage.
The previously known measurement procedures and cables are expensive and have limited usefulness due to the length of application. Detectability with aid of electrical procedures is good, and the determination of the leakage location is possible with simple means. However, the known procedures of this kind are susceptible, particularly to electromagnetic disturbances. In addition, the possible length is strictly limited by the transversal conductibility of the insulation materials. With respect to location of hydro-carbonbased liquids, it is possible to locate these as well by means of changes of the dielectric characteristics of conductors at the location of the leakage. However, there are problems due to the fact that the liquids to be detected are very similar to the insulation materials particularly with respect to the dielectric characteristics. Reliable location is thus possible only with great wetting lengths or over small lengths of measurement cables.
The purpose of the invention is to provide a cable for detecting location of liquids, which cable rapidly and reliably indicates a presence of liquids of varying kinds and thereby allows a precise location of the leakage over a significantly greater distance than has hitherto been possible.